Tumbler type clothes-washing machine



Oct. 25, 1966 B. PANKl-:R

TUMBLER TYPE CLOTHES-WASHING MACHINE 2 Sheets-Sheet l Filed April 27, 1964 INVENTOR W2k/Q91? Yer BYWV 9% f@ ATTORNEYS Oct. 25, 1966 B. PANKER 3,280,504

TUMBLER TYPE CLOTHES-WASHING MACHINE Filed April 27, 1964 2 Sheets-Sheet 2 INV ENTOR 32:17 Pa hier Wm, VWM

ATTORNEYS United States Patent O 3,230,604 TUMBLER TYPE CLTHES-WASHlN-G MACHINE Bent Panker, Ravnebof Eregnerodvei, Allerod, Denmark Filed Apr. 27, 1964, Ser. No. 362,717 Claims priority, application Denmark, May 2, 1963, 2,075/ 63 8 Claims. (Cl. 68146) This invention is concerned with a motor-driven domestic machine, especially a clothes-washing machine, comprising a rotary working drum, which has a detachable cover and which is detachably mounted with a wholly or su'bstantially horizontal axis of rotation and supported on supporting rollers journaled in a frame, of which rollers at least one is a drive roller.

This invention has amongst other things for its object to provide a machine of the said type which can be produced in a particularly simple and economical way, and which is easy t-o operate and economic in service. According `to the invention the drum and its cover are made of heat-resistant plastic, and the body of the drum is substantially cylindrical with a diameter mainly equal to its length.

The prescribed design and dimensioning of the drum as well as the use of plastic as `the material for the components mentioned above are important in that during a washing operation the drum is only subjected to a small heat loss and that, consequently, it can operate with a relatively small amount of washing lye. In the prior art drums made of metal it has been necessary to to give the drum a rather large diameter in order that it may contain an adequate amount of lye which will not -be cooled too quickly during the washing process whereby the washing effect would be reduced. The great diameter of the drum implies in the prior art machines that it must have a relatively low rate of revolution and, consequently, complicated and expensive transmissions will have to be used between the motor and the drum to ensure the required low number of revolutions. In contrast thereto the machine according to the invention may require only a simple 'belt or chain transmission between the motor and the drive rollers of the drum whereby the price of manufacture of the machine can be kept so low that the purchase thereof will lie within the means of almost anybody.

Further advantages and characteristics of the invention will appear from the below description in which reference is made to the accompanying drawing, where FIG. l is an elevation of an embodiment of a machine according to the invention and comprising a drum especially designed for clothes-washing,

FIG. 2 is an inverted plan view of the machine illustrated in FIG. l where the base plate, not otherwise shown, of the machine has been removed,

FIG. 3 is a longitudinal section through a washing drum of modified construction,

FIG. 4 is a section taken on line IV-IV in FIG. 3, and

FIG. 5 is a section on a larger scale of a preferred embodiment of the drive rollers of the machine.

The machine shown in FIGS. l and 2 consists of a frame or housing 1 and a drum 2. The drum 2 has a cylindrical or slightly conical body portion 2a, a conical shoulder portion 2b, and an externally threaded neck 2c, the outer end of which is open. At the upper and lower ends of the body portion 2a the drum is provided with two cylindrical running surfaces 3 which in the embodiment shown have a diameter slightly greater than that of the body portion of the drum.

By means of its runing surfaces 3 the drum is supported on four supporting7 rollers 4, of which two are secured to a shaft 5 journaled in the machine frame 1 and connected with the drive motor of the machine. In the embodiment shown the two other rollers 4 are freely rotatable supporting rollers. The running surfaces 3 are preferably knurled, and the rollers 4 are made of, or consist at least on their surfaces engaging the running surfaces 3, of a material having a suitably high friction.

The front part 1a of the frame or housing 1, wherein the shaft 5 and the two s-upporting rollers 4 are mounted, is at the top closed by means of a transverse wall 1b rounded to conform with the shape of the drum 2, in which wall there are four cut-outs, not shown, for the rollers 4 whereby the drum is supported by said rollers without contacting the frame.

The rear part 1c of the frame 1 is shaped as a hood which supports and covers the electric drive motor 6 of the machine, said motor being mounted on a transversally extending plate 36, see FIG. 2, which in turn is secured to the frame. A stirrup-shaped handle 7 by means of which the frame can 4be lifted and conveyed, is secured to the upper side of the frame 1. To the front end of the handle 7 there is secured a stop member 30 for the drum, the axis of which has a slight rearwardlydirected inclination so that the bottom of the drum rests against the stop member. This stop member may for example by a polished slightly curved metal plate or knob or a rotatable roller or ball so that the friction between the bottom of the drum and the stop member is small. As indicated in FIG. 3, a wearing ring 35 of, for example, nylon is embedded in the bottom of the drum for engaging stop member 30.

The shaft 5 is driven from the motor 6 through a belt drive, a pulley 9 being secured to the motor shaft 8, and a belt ttl, preferably a toothed belt, connects the groove of the pulley 9 with a pulley 11 on the shaft S.

At either side of each roller '4 the shaft 5 is journaled in a bearing 31 secured to the frame 1, lso that the shaft is safely supported and prevented from vibrating. With a view to compensate for disalignments, if any, in the four bearings for the shaft 5, for example on account ot' minor deformations in the self-contained housing or frame 1 preferably made of plastic, the shaft is divided into two halves which are connected by means of a short elastic coupling 32 of for example rubber or nylon, said coupling operating as a universal joint. The two nondriving supporting rollers 4 are similarly journaled in bearings 31 secured to the frame 1.

In t'he embodiment shown the drum 2 is slightly conical so that the running surface 3 closest to the neck portion has a slightly greater diameter than the running surface at the bottom of the drum. In view hereof, the shaft 5 forms a small angle with the axis of the two nondiiving supporting rollers 4. If both pairs of rollers 4 were driven by the motor 6, the latter could be so disposed t'hat the center line of its shaft 8 halves the angle between the two driven shafts which would red-nce the wear on the two belts resulting from the disalignment between said shafts.

in its body portion 2a, the drum 2 lis provided with longitudinally extending internal beads 20 which are integral with the drum wall. In the .embodiment shown there are four beads 20. The beads which operate as carriers for the laundry loaded into the drum, Vhave two inwardly extending inclined side faces 21 which in a cross section at right angles to the drum axis form an angle of about with one another. The internal longitudinal extending edge of the beads between the two side walls 21 are in longitudinal section of wave form with wave lcrests 22 and wave troughs 23. IDu-ring rotation of the drum the troughs 23 operate as channels which ensure circulation of washing lye about the outer side of the laundry engaging the drum Wall and bead edge. Instead of the relatively ygreat and few beads, shown, the drum could also be provided with a plurality of small ribs or tins of correspondingly smaller depth.

The drum 12 shown in FIGS. 3 and 4 is mainly designed as t-he drum 2 shown in FIG. 1, i.e. with a slightly conicalbody portion 12a, a shoulder portion 12b and a l cylindrical neck portion 12C and two running surfaces 13,

by means of which the drum can be supported on and driven by rollers corresponding to the rollers 4 shown in FIGS. 1 and 2. Whilst the drum 2 shown in FIG. 1 is intendedduring operationto be closed by means of a screwed-on cover, not shown, the drum 12 is closed by or clamp 15 swingably connected with the drum is pressed against the edge of the dr-um opening in the neck portion 12C. An elastic packing 16, for example a rubber ring, is provided between the edge of the drum opening and a recess in the edge of the cover.

A widened portion 17 at the middle of the clamp 15 is hollow and contains aspring-loaded thrust pad 1S whic-h protrndes from the widened portion 17 so that the spring keeps the pad pressed against the center of the cover 14 with a suitable constant force. In so doing, the -cover is pressed against the mouth of the drum neck. The widened portion 17 may be shaped as a handle.

The clamp 15 swings on two pins 19 rotatable in the l neck portion 12e` and se-cured to the clamp. The pins 19 may be protected against unintentional withdrawal from t-he drum neck, for example by means of a transverse pin or the like which engages a circumferential groove in the pin 19. As the center of the hemisp'herical cover 14 is disposed substantially in the plane of the drum opening, the clamp 15 will, on being swung aside away from the yposition shown in FIG. 3, withdraw from the surface of the cover whereby the spring pressure exerted on the thrust pad 18 decreases. Thus, in its swungout position the thrust pad can go quite clear of any bead on the edge of the cover, as shown in FIG. 3, and in its swung-up locking position it can extend closely to the cove-r.

The drum 12 is prov-ided wit-h four internal beads' or ribs 33 which extend radially from the drum wall in the body portion 12a thereof towards the axis of the drum. In the longitudinal direction the bead-s extend in the embodiment s-hown from the upper end of the body portion 12a near the running surface 13 down to the bottom 34 of the drum and through a rounded portion merge evenly into t-he bottom. Like the beads 20 shown in FIG. 1, the beads 33 operate as carriers for laundry loaded into the drum. The embodiment of the beads shown in FIGS. 3 and 4 is particularly expedient when the drum is produced by injection molding and in two parts, namely the bottom portion and the neckportion with theshoulder portion, respectively. The number and theshape of the beads may differ from those shown, and similar beads may also be provided on the shoulder portion of the drum.

The drum and the cover are preferably made of plastic which is heat-resistant, i.e. stands temperatures of 100 C. or above. Such mate-rials are for example polypropylene or ABS (an acrylonitrile-butadiene-styrene copolymer). The drum may be produced in any suitable manner, for example by injection molding or by blowing, if desired. The cover and/or the drum, or at least part thereof, may expediently be made of a transpa-rent material so as to atord the possibility of watching the washing process from lthe outside. The drum may, as stated above, be made of two parts, namely a body portion and a neck portion with the associated shoulder portion, respectively. If so, particularly attractive effects may be obtained in that the two portions and, if desired, also the cover may be of different colors, or one portion may be transparent, so that the progress of the washing j a hemispherical cover 14 which by means of a handle f process may be robserved from the outside,fand another portion may be opaque. may be interconnected in a known manner, for example by .friction welding or by the kso called fusion welding, wherein the two portions are pressed against e-ach other, and the materials in the joint are locally dissolved by means of a `suitable solvent so that the two materials can fuse together.

In another embodiment, not shown, of the machine according to the invention, the -body portion of the drum may be smooth, and a web or shell of perforated plate, for example metal plate, may be secured slightly spaced from the inner side of the drum wall, whereby a liquid space is provided between the shell and the drum wall. On this shell provision may be made for infernal beads or` ribs which, if the machine is designed as awashing machine, operate as carriers for the wash. In other uses of the machine, the internal shell may be designed in an analogous manner according to the purpose of application. For example in the case of a potato peeling machine it may be provided with knife members.

FIG. 5 shows a preferred 'embodiment of the supporting and driving rollers 4 purely diag-rammatically shown in FIGS. l and 2. The roller shown in FIG. 5 which is secured to a shaft 5, consists of a body 41 which for example may `be produced by injection molding of a suitable plastic. The body 41 is secured to the shaft 5 by means of a cotter pin 42. In its cylindrical surface the roller body 41 is provided with three circumferential grooves 43 interspaced Ialong the length of the roller. A wearing ring 44 of polyurethane is secured in each of the grooves with the cylindrical surface of the ring projecting from the surface -of the roller body 41 so that the surfaces of the three rings 44 constitute the wearing face of the roller in contact With the corresponding running surface on the drum of the machine. One or more, for example three, pins 45 have Ibeen driven axially through the roller body 41 and the wearing rings 44 so as t-o-retain the rings in their grooves 43.

The rings 44 of polyurethane have `proved to have extremely good wear-resistance in conjunction with the knurled running surfaces of the drum, and it is consequently possible to give the rings a comparatively small diameter and thereby ensure a good gearing ratio between the shaft 5 and the drum. When mounting the rings 44 in the groove 43, it is advantageous to use a conical mounting mandrel, the greatest diameter of which corresponds to the louter diameter of the roller body 41, and which during the mounting operation is placed coaxially with said body, for example located by the projecting hub thereof, and the elastic rings 44 are then successively slid over the mandrel and on to the roller 41 yuntil they slipk 31, and out through a number-of ventilation openings 38 in the rear wall of th'e frame or housing 1.

The invention is not limited to the embodiments herev shown and described which may be varied in a multitude Iof ways withi-n the scope of the invention. It is also possible to apply the invention to machines for purposes other than clothes-washing, for example, as mentioned, for peeling potatoes and other fruits, for churning butter, or for mixing different solidV and liquid substances. In the embodiment shown, the drum is supported on supporting rollers, of which only some are driven rollers, but if required it would b'e possible, as mentionedvabove to let all these rollers be -driven rollers. It would also be possible to support the drum on only two supporting rollers in combination with a journal bearing at the center of its bottom. This journal bearing might be in the shape of a drive member so that the drum can be driven therethrough.,

The two portions of the drum v The machi-ne according to the invention, here described and shown in the drawing, is particularly suitable for doing small loads, i.e., that it preferably has a capacity of 11.5 kg. of dry clothes. The structure of the machine renders a particularly simplified and economical manufacture possible. It differs from the conventional drum washing machines i-n that it does not consist lof a container with ly'e and a perforated drum rotatable therein for the reception of the laundry but only a closed drum which contains both the laundry and the lye. Previously such machines have been suggested comprising a single drum, but in these machines the drum is made of metal. The drum and the drive motor including the transmission have in some cases been built together to form an integral structure, whilst in other prior art machines the driving unit is very complicated because the number of revolutions of the drum is relatively small whi-ch involves different disadvantages which have been overcome through this invention.

Thus the machines for use particularly in washing small loads comprised no arrangements for heating the lye du-ring the washing operation proper, and the machines made of metal will therefore quickly be cooled so that the washing property of th'e lye will be deteriorated. The prior art machines wherein the washing drum and the drive unit are built together to form an entity are moreover not handy and practical to operate and store.

In the machine according to the invention, the drum is a separate machine part without fixed connection with the drive unit of the machine, and the drum, if desired, can be stored separately in a vertical position. The provision for a handle at one end of the drum makes it possible to conv'ey the drum in an especially easy manner, also when it is wholly or substantially full. It is easy to lift the drum from the frame or base portion in that one hand can readily get hold of the slightly inwardly curved bottom of the drum, whilst the other hand may lift the drum, for example by means of the -above mentioned handle. As the handle, as shown in FIG. 3, is disposed almost directly along the outer side of the cover, when the drum is closed, the risk of accidents by a finger or a part of the garment, for example a sleeve, bei-ng jammed betw'een the cover and the handle is avoided. The hemispherical shape of the cover effectively counteracts the possibility of the laundry loaded into the drum getting into contact with the innerside of the cover which, if so, would `be scratched by for example buttons, safety pins, etc., in the clothes. The slightly rearwardly inclined position of the drum also contributes thereto.

The use of plastic as a material for the drum remedies the above mentioned drawbacks arising from the quickly decreasing temperature ofthe lye in the prior art machines comprising a metal drum. The plastic is possessed of considerable heat-insulating properties and consequently affords the possibility of attaining satisfactory washing results without using a built-in heating arrangement in the machine, and this feature makes it possible to manufacture the machine at very low costs. The size and dimensioning conditions of the drum and the design Ithereof with an opening at one end bottom makes it especially expedient to produce the drum of plastic.

It has proved that a drum according to the invention having a capacity of about 15 liters and having a load of about 5 liters of hot washing lye with a temperature of 80 C. will in the course of about 20 minutes only dissipate so much heat that the temperature of the lye decreases to about 70 C. In prior art machines comprising a metal drum it has been necessary, for the purpose of avoiding too great a temperature drop during the washing operation, to use a relatively large amount of washing lye and, in consequence thereof to give the drum such a large diameter that its number of revolutions-when out of regard to the washing effect the centrifugal force must not be too great-must be so small that mechanical gears of complicated construction are required, also because heretofore it has been necessary to give the drive rollers a rather large diameter lest they should be Worn too quickly.

In a machine according to the invention, a drum having a diameter of about 300 mm. is applicable, and it is, therefore, possible to use such large number of revolutions for the drum that a simple belt or chain drive may be used l as power transmission between the motor and the drive rollers. When using rollers having wearing faces of polyurethane, which has proved to have particularly great wear-resistance when cooperating with embossed grooves in the surface of the drum, it will become possible to make the rollers with a small diameter so that even with the small drum diameter, a large gearing ratio between the rollers and the drum is attained.

The safety arrangement for the cover of the drum affords the possibility of the drum being brought into rotation in an expedient manner. As a drive member for the drum it would also be possible to use a single roller which is so disposed as to engage lthe bottom of the drum and rotate the same by friction under the inuence of the weight of the drum and the load thereof, and at the same time the roller will operate as an end stop for the displacement of the drum in the axial direction.

What I claim is:

1. A single-drum clothes washing machine, comprising a frame, a driving motor mounted on said frame and including a drive shaft, a plurality of supporting rollers rotatably supported in said frame with substantially horizontal axes, speed reduction gears means mounted on said frame and connecting said drive shaft with at least one of said supporting rollers, an imperforate washing drum detachably supported by said supporting rollers, said washing drum comprising a substantially cylindrical body portion the diameter and length of which are substantially equal, said body portion being closed at one end, a neck portion integrally connected to said `body portion opposite the closed end thereof and having an axially facing opening at its end opposite said body portion, a cover for said opening and means secured to said neck portion for detachably clamping said cover against the end of said neck portion to close the opening therein, said body and neck portions and said cover being made of heat-resistant plastic material.

2. A washing machine as claimed in claim 1 in which said supporting rollers comprise wear elements for engaging the outer lateral wall of said drum body portion, said wear elements being made of polyurethane.

3. A washing machine as claimed in claim 2 wherein said rollers comprise a body journaled in said frame and provided with plurality of circumferential annular grooves, and said wear elements are shaped as separate rings of polyurethane held within said grooves and projecting from the circumference of said roller body.

4. A washing machine as claimed in claim 1 wherein said frame is made of plastic material, and at least two of said supporting rollers are secured to substantially coaxial shafts interconnected by flexible coupling means, one of said shafts being connected to said speed reduction gear means at the shaft end remote from said coupling means.

5. A washing machine as claimed in claim `4r wherein said coupling means consists of a bushing of elastic material secured with a tight t to a free end of each interconnected shaft.

6. A washing machine as claimed in claim 1 wherein the axes of said supporting rollers are slightly inclined, and stop means for engaging the closed end of said drum body portion is pro-vided on said frame.

7. A washing machine as claimed in clairn 6 wherein said frame comprises a front portion including bearing means for said supporting rollers and a transverse upper wall having yapertures therein for said rollers, and a Irear portion contiguous with said fron-t portion and projecting above said portion in the form of a hood, means for 7 supporting said drive motor below said hood, said stop means for the drum body portion being provided on the outer side of said hood.

l8. A Washing machine as claimed in claim 1 in which said drum body portion is slightly ltapered, and said supporting rollers are arranged in pairs each having a a, common axis of rotation, said axes of rotation including Y a small angle between them.

References Cited by the Examiner v UNITED STATES PATENTS 166,579 8/1875 A-tWOOd 68-146 567,446 9/ 1896 Baron 220-96 X 732,913 7/1903 Andresen 68-142 8 Hofrken 68-146 Mammen 68442 Sharp 68-144 Dewhurst 68-140 X Zimarik 68-144 Zimarik 68-140 Wellman 68-144 X Tellander 220-55.7

Smith 684146 X FOREIGN PATENTS Great Britain.

RVING BUNEVICH, Primary Examiner. 

1. A SINGLE-DRUM CLOTHES WASHING MACHINE, COMPRISING A FRAME, A DRIVING MOTOR MOUNTED ON SAID FRAME AND INCLUDING A DRIVE SHAFT, A PLURALITY OF SUPPORTING ROLLERS ROTATABLY SUPPORTED IN SAID FRAME WITH SUBSTANTIALLY HORIZONTAL AXES, SPEED REDUCTION GEARS MEANS MOUNTED ON SAID FRAME AND CONNECTING SAID DRIVE SHAFT WITH AT LEAST ONE OF SAID SUPPORTING ROLLERS, AN IMPERFORATE WASHING DRUM DETACHABLY SUPPORTED BY SAID SUPPORTING ROLLERS, SAID WASHING DRUM COMPRISING A SUBSTANTIALLY CYLINDRICAL BODY PORTION THE DIAMETER AND LENGTH OF WHICH ARE SUBSTANTIALLY EQUAL, SAID BODY PORTION BEING CLOSED AT ONE END, A NECK PORTION INTEGRALLY CONNECTED TO SAID BODY PORTION OPPOSITE THE CLOSED END THEREOF AND HAVING AN AXIALLY FACING OPENING AT ITS END OPPOSITE SAID BODY PORTION, A COVER FOR SAID OPENING AND MEANS SECURED TO SAID NECK PORTION FOR DETACHABLY CLAMPING SAID COVER AGAINST THE END OF SAID 